insider
1
Does this stuff really improve your eyesight? How does it work?
Lutein. Nobody really knows yet whether it works. Some early research indicates it may improve your eyesight.
http://vm.cfsan.fda.gov/~frf/forum01/A143PPO.htm
You get any of that? Me neither. 
It’s a “dietary supplement”, so it’s covered under different FDA rules. It doesn’t need FDA approval, in other words. Consume at your own risk.
http://vm.cfsan.fda.gov/~dms/supplmnt.html
You want to know anything else, Google is your friend. 